Dash-pot.



PATENTED AUG. 7, 1906.

H. M, GRAN DASH POT. APPLICATION FILED JUI IB 5. 1905. RENEWED FEB. 13

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No. 823,091". PATENTBD AUG. 7, 1906. H. M. CRANE.

DASH POT, AP PLIUATION FILED JUNE 5. 1905. RENEWED FEB. ql3, 19Q6.

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[1 11 1 HI IHhUH] IW Jm tnrrrnn srarns earner orrrcn HENRY M. CRANE, NEW YORK N. Y., ASSIGNOR TO WESTERN. ELECTRIC- COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

. are. seaoei.

Specification of Letters Patent.

Patented Aug. '7, race.

Application filed June 5, 1905. Renewed February 13, 1906. Serial No. 380,915.

' To aIZZ whom it may concern.-

pot whic will be absolutely self-contained .and Waterproof, so that it may be mounted in the most exposed positions. It has also been my aim to avoid suction between the piston of the dash-pot and the ends of the cylinder in order that the acceleration of the piston u on starting may be as rapid as possible an to provide an air-cushion at each end of its stroke to regulate said piston, and thereby revent its being brought violently against t e end of the cylinder.

In the dash-pot of my invention I provide a closed cylinder within which a piston is adapted to reciprocate, the pist0n-rod assing through the cylinder to the exterior t 1er'e-j of.. Covered assages are provided in association with tile cylinder having openings at their ends communicating with the cylinder, said passages openin into the cylinder intermediate said end. oles. The air is thus allowed to flow through the passages and end holes, respectively, into the cylinder at the rear of the piston when moving in either direction, so as to prevent suction of the piston and allow thefsame'to accelerate rapidly at the beginning of its stroke. I also provide check-valves within said passages, which are adapted-to prevent air from assing from the cylinder through the end ho es into the passages, connected therewith. Thus when the pistonpasses the central opening, moving in either direction, it prevents the flow of air into the portion or end of the cylinder immediately before it, and as the check-valve associated with the hole'in that end of the cylinder is closed an air-cushion is furnished for the piston during the remainder of its travel in such direction.

I will describelmy invention more particularly by reference to the accompanying drawings, which illustrate the preferred embodiment thereof, reserving for the appended claims a statement of the parts, improve ments, or combinations which I consider novel with me. I

Figure 1 is a vertical sectional view of the dash-pot embodying myinvention applied to other form of my invention.

The same letters of reference designate the same parts throughout both; figures of the drawings.

The drawings illustratethe application of semaphore-vane such as is'fe'rn loyed in signaling systems of ships. The flame a of the mast of a vessel and carry at its u per end the dash-pot, which wouldact as a rake for the moving solenoid-core, a'nd'the semaphorearm 0 erated thereby.

frame of the solenoid at the upper end there of, a piston 0 being provided within the cylinthereof. The piston-rod 0 extends through be connected with a semaphore-vane, the up- Re erring first to Fig. 1 the cylinder 5 of the dash-pot is preferably secured to the the cylinder to the exterior thereof andmay.

a solenoid, and Fig. 2 is a sectional. view of anmy invention to a solenoid controlling asolenoid would in practice be secured to the 8o der ada ted tomove with the core of the so;

lenoid, eing preferably attached to the end er end wall of the cylinder forming a bear 1 mg for the piston-rod. The sema here-vane would thus be caused to partake o the movement of the solenoid-core.

The side wall of the cylinder is provided with holes (1 d at opposite ends thereof, and

inder and having openings communicatin with the holes (1 d lead from said holes an open into the cylinder near the middle of the slde wall thereof, said passages preferably communicating with a hole e near the midholes referred to, the Wall and cover forming the air-passages referred to. piston begins its movement in either direction the Wall of the cylinder air will be permitted to fiow through the opening e into one of the passages ac through the-end opening in the c linderfcommunicating with said passage to t 16 rear of the moving piston, preventing covered air-passages e c, external to the cyl- I Thus when the dle ofthe' side Wall. A cover is secured to I the outer surface of the cylinder over the.

and until it passesl the central opening e in -15 intot e c" f tion of e c'y inder imme 40 the wall of t suction of the piston and allowing the same to start uickly with rapid acceleration, in will. valve 9 near the end opening in the cylinder connected with such passage. Adjacent to each end hole is rovlded a partition h, extending between t e cover f and the side wall of the cylinder and having an opening therein in which the check-valve associated With 10 such end holemay be mounted. Each check-valve is adapted topermitair to flow through thecentral "opening a into the passage in which it is secured and through the er: "0 e connected with such passage der, but to prevent air from flowing in the op osite 'direetienbfrom the cylinder through t e end opening with which i'l/ 'l'S associated and into the passage. connect- 'e'd with suc'h opening. Thus when the piston traveling in either direction passes the te'ly before the iston is cut oil and an EiP'CHShJOh provided or the piston during the balance of its movecentral 0 enin e the supplglgfair t'o 'thep'or- 2 5 merit in such direction.

The operation of the dash-pot may "be briefly described as follows: "in the drawings the core of "the solenoid is shown attracted and Within the helix of the solenoid with the o piston at the lower end 'ofth'e cylinder. In

' this position of the parts the semaphore-vane would be in a signalingposition. solenoidbecomes deenergl'zecl, the core is re leased, and the Weight of the semaphore-arm 3 5 would withdraw the core from "the helix and move the piston tothe upperend 'ofthe cylinder, as indicated in dotted "lines in Fig. l. As "the piston begins its upward movement and until it passes the central opening e. in e ylinder the air is caused to new from the cylintlerthrongh'tlre opening a in the Wall thereof, through the passage '0 and end opem'ng 'd, -ii1to the cylin er at the rear of the piston, thus'preventir-ig any sect'ion-whichwofild reterdtne movement e'l'the piston at the be inning oi'its's'troke. A-fter the piswn trsvels be 0nd the opening a it is cushioned for the ba ance of its stroke, since the clie'ck ya'lve in the assage e-prevents'the 5o esea'p'e'ofthe air from t e portion of the cylinderiinine'diately before the piston 'hy way o'fthe endhole the jmodified form of m invention in 2 I provide c'overe passages in the'form 'ofapipes d (2? external to the cylind'ei' a'n'd'lea from the endholes d (1, Te

spectively, in thejeylinder, said pipes '0 ening intothe cylinder near the rind l e e the wall thereof, each beingpro ilied with-a "he operation of the'dashpot as thus medifiee "would b'esubstentially the same as'deserflied'with respectte Fig. '1. .Te'laim- 'I v 1 In a dash-pot, the combinationwitha I cylinder, ofa piston within the cylinder, a

en the piston-rod passing through the cylinder, the

y 1 cylinder having holes therein at its 0 osite passage e e I provide a check pp through said end holes, but to permit air to flow in the opposite direction throu h the passa es and end holes into the cylinder; where y the piston is cushioned at both ends of its stroke. 2. In a dashot, the combination with a cylinder, of a iston within the cylinder, a piston-rod passin through said cylinder, the wall of thecylin er havin a hole therein at each end and near the mid e-thereof, covered passages external to the cylinder leading om said end holes to the central *holefihe air flowing throu h said central hole-end passages into the c-y inder to prevent sue-tionof the piston, and check-valves adapted to pre vent the'entryof air to the passages *thnsirgh said end holes; whereby the pisten di m? it passes said central opening is provided an air-cushion.

3. In a dash- 'ot, the comhinttti-en with a cylinder, of a piston within the "linden piston-rod passing through "the eyin-ider, the wall ofthe cylinder havingighe'les etonpesiee ends and an opening near t e niidd'le't nereei, an in'closing cover secured "to the enter sen face of the cylinder over said openings te -therein at each end and near the thereof, a 'cover'secured to the outersnrlaee of said cylinder-over said openings tdiorm an air-chamber, partitions at opposite ends of said chamber near the end operings ex tending between the 'cyli der-w I1--= 3 ethcover,- said partitions "hayin Openings s 1n, and check-valves within said openings adapted to prevent air from entering the. chamber through said end openings bdt *to "rmit air 'to'lio'wthrong'h said central openmg into said chamber *andtl'lrough'theenrl openings'into, the cylmder "whereby an =aircushion is provided'for the ,pistonat 'each en'il .o'f its'stroke. v I

'5. In a dash-pot, the "combihation'with a cylinder, of a iston therein, a pistonro'd passing throng the cylinder, the cylinder having holes therein at its opposite ends, covered passages leading. from said holes and 0 ening into the cylinder, the iston in elther stroke after passing the o1nt Where said assages open into the cylin er tpreventin 't e flow of air into the portion 0 the cyl in er in front thereof, and checkalves adapted .to prevent the entry of air to said passages through said end holes; whereby the piston-is cushioned at both ends of its stroke.

6. In a dash-pot, the combination with a cylinder, of a piston within the cylinder, a piston-rod connected with said piston, covered passages having openings at their ends communicating with said cylinder, said assages opening lnto the c linder interme iate said en openings, and c eck-valves adapted to prevent air from entering said passages through said end openings, but to permit air to flow in the opposite direction throu h said. passages into t e cylinder; whereby tie piston is cushioned at both ends of its stroke.

7. In a dash-pot, the combination with a cylinder, of a piston within the cylinder, covered passages communicating with the cylinder at the end thereof, said passages opening into the cylinder intermediate the ends thereof, and check-valves associated with said passages.

In Witness whereof I hereunto subscribe my name this 18th day of April, A. D. 1905.

HENRY M. CRANE.

Witnesses:

GEORGE A. HAMILTON ALBERT M. BULLARD. 

